| database |
| deborate |
| dB | decibel |
| defense-in-depth |
| defoaming |
| anddeg; or deg | degree (plane angle) |
| DOF | degree-of-freedom |
| Canddeg;;Canddeg; | degrees Celsius; Celsius degrees (for temperature change or difference) |
| Fanddeg;;Fanddeg; | degrees Fahrenheit; Fahrenheit degrees (for temperature change or difference) |
| K (anddeg; not used) | degrees Kelvin (absolute) |
| anddeg;R | degrees Rankine |
| demultiplexer |
| DOD | Department of Defense |
| DOE | Department of Energy |
| DER | Department of Engineering Research |
| DHS | Department of Health Services (California) |
| DPH | Department of Public Health (county) |
| DOT | Department of Transportation |
| DLAP | Department-Level Administrative Procedure |
| DNB | departure from nucleate boiling |
| DNBR | departure from nucleate boiling ratio |
| DBA | design basis accident |
| DBD | design basis document |
| DBE | design basis earthquake |
| DBM | Design Basis Management |
| DBT | design basis threat |
| DBV | design basis vehicle |
| DCN | design change notice |
| DCP | design change package |
| DCR | design change request |
| DCM | Design Criteria Memorandum |
| DE | design earthquake |
| DFE | design flood event |
| dew point |
| dewater |
| DCISC | Diablo Canyon Independent Safety Committee |
| DCL-98-XXX | Diablo Canyon Letter |
| DCPP | Diablo Canyon Power Plant |
| DCPRA | Diablo Canyon probabilistic risk assessment |
| DET | diagnostic evaluation team (NRC) |
| dia | diameter |
| DEG | diesel engine generator |
| DG or D/G | diesel generator |
| DBW | differential boron worth |
| DP or delta P | differential pressure |
| DPV | differing point of view (NRC) |
| DPO | differing professional opinion (NRC) |
| DRPI | digital rod position indicator |
| dc | direct current |
| DR | Discrepancy Report or Deviation Report |
| dpm | disintegrations per minute |
| dps | disintegrations per second |
| D.C. | District of Columbia |
| DC | District of Columbia (in address with zipcode) |
| DPR | Division of Power Reactors (AEC) |
| DTC | doppler temperature coefficient |
| DDE | double design earthquake |
| DER | double-ended rupture |
| down time |
| downstream |
| downwind |
| DES | Draft Environmental Statement (NRC) |
| drawdown (noun or adj), draw down (verb) |
| DLF | dynamic load factor |
| dyn | dyne |
